The aim of the proposed research is to examine the functional aspects of sensory-motor integration via a study of the influence of acoustic information processing on the regulation of vocalization. Auditory feedback not only plays a significant role in the ongoing control of vocalization in the mature organism, but is especially important in the proper development of species- specific vocal patterns, including those of human speech. The biosonar system of the mustached bat, Pteronotus parnellii, has proven strategically advantageous for the study of audition and vocalization. In parrticular, this sutdy exploits the fact that mustached bats control very percisely the frequency of their biosoonar signals, based upon the frequency information present in echoes. This behavior, know as "Doppler-shift compensation", involves the production and reception of comparatively simple acoustic signals easily mimicked for experimentation which, however, contain acoustic elements similar to those used in human speech. These signals and their underlying motor patterns are sterotyped and repetititvely produced, both in nature and via microstimulation of brain. This proposal is designed to examine the rose of the anterior cingulate cortex in the fine control of the frequency of emitted sounds, such as occur for Doppler-shift compensation during target-oriented flight. Functional organization of the anterior cingulate cortex based on the characteristics of electrically elicited vocalization and upon response properties of neurons to synthesized biosonar sound will be explored. Detailed examination of projections to anterior cingulate cortex, particularly from auditory cortex, and the study of efferents from anterior cingulate cortex will be pursued via the horseradish peroxidase and microstimulation techniques. This phase of the study will explore the type, source and organization of the acoustic influence on control of vocalization via the anterior cingulate cortex.